my macpro 2x2.66 first gen just took a dive and I AM TERRIFIED- as I am broke right now!!! one and a half years ago I pulled a drive out of my macpro and put it in a box for long term storage, I stored it properly, it had a lot of older recordings on it and I didn't need them in the comp, so I took out the drive and put in a new larger one. last night I pulled out that drive and decided to pop it in and pull some older songs up. as soon as I started the computer the fan went totally crazy, I've never heard it spin that much or that fast in 3 1/2 years with this comp, it worried me immediately! she just went to a gray screen and stayed there, then nothing else happened so I powered down. I took the drive back out and restarted the comp. keep in mind that this drive had been formatted on that actual computer and used on that computer for a year and a half before being removed to make room for a larger drive. it has NEVER been attached to another computer, EVER. I powered her up and got a folder with blinking a question mark. so I tried a restart, no luck, was going to try and boot from the install disc only to find that my computer would not recognize the DVDRW drive, would not even open it. forced the drive open using a paperclip and inserted the statup disc, nthing, it would not even recognize that the drive or the disc was there. stripped out all 3rd party hardware, pcie cards, USB, Firewire etc, all HD's other than the boot drive, tried again, no luck. the computer itself will not recognize any of the HD's, DVDRW or any internal hardware. reset PRAM, nothing. so I try restarting the computer in target disc mode, no luck, just a gray screen with the folder and question mark. then I break out my laptop and start it, (macbook), in target disc mode so I can treat it like a bootable external drive, FW400 connected to the tower. once the macbook is in target disc mode I start the macpro tower, and she see's the bootable external drive and fires right up. running off the macbooks drive like it was just an external FW drive. I run for a few minutes and do all the diagnostics I can, nothing though. so I then insert my OSX install disc into the macbook dvdrw drive, it recognizes the disc and loads into the bootable disc from the FW macbook drive. at this point I run disc utility on the tower and it will not see any of the drives in the tower(all 4 are re-inserted at this point). then I run the apple hardware test from the macbook under FW target disc mode, it shows the proper specs of the tower and recognizes all ram and processors accordingly, the tower looks fine but will not recognize the internal HD's or DVDRW drive, no internal hardware peripherals are being seen. I run the apple hardware test twice and it passes both tests perfect.(extended test). I am so lost as to what to do next. a few odd details. if I just power it up it goes to the folder and question mark icon. if I start while holding down the option key for a booy menu it will stay at the blank grey screen, no folder with question mark, no icon of any kind. the computer functioned perfectly when booted from the macbook in Target disc mode, all processors and ram functioned and checked out perfectly. please suggest anything you know that I have not tried yet, I really cannot afford this right now. mac pro 2x2.66 ghz with 7GB Ram-OSX 10.5.7 for the record.